EyeWorld India March 2018 Issue

49 EWAP DEVICES March 2018 by Michelle Stephenson EyeWorld Contributing Writer New devices in cataract surgery continued on page 50 The ApertureCTC device is deployed on the anterior capsule in preparation for capsulotomy construction. Source: Mark Packer, MD Alternatives to femtosecond lasers are entering the marketplace N ew devices for cataract surgery are entering the marketplace that have benefits over femto- second lasers for capsulotomies, according to some surgeons. “One of the benefits of the femtosecond laser is that it provides a perfectly round, perfectly centered capsul- otomy,” said Mark Packer, MD, Boulder, Colorado. “However, scan- ning electron micrographs of that cut edge of the femtosecond cap- sulotomy have shown that it looks craggy and irregular, and capsular strength testing has shown that femtosecond laser capsulotomies are not as strong and resistant to tearing as manual capsulotomies.” Several companies have begun looking at ways to make a perfectly round capsulotomy that is stronger than a femtosecond laser capsul- otomy and is less expensive than buying a femtosecond laser. Zepto The Zepto capsulotomy system (Mynosys Cellular Devices, Fre- mont, California) is a device for making a capsulotomy. It consists of a thin nitinol wire loop, which is the element that gets hot and does the cutting. The loop is sur- rounded by a silicone plastic shell connected to a suction tube. “The idea is that you introduce this into the eye through a 2.2-mm to 2.4-mm incision,” Dr. Packer said. “The silicone shell squeezes down. There’s a push rod inside the sili- cone sleeve that you use to expand the ring to a circle, and nitinol has shape memory, so it goes back to a circle. You pull that push rod out, retract the push rod, turn on the suction, and the whole thing sucks itself down onto the anterior cap- sule. The manufacturer talks about being able to align this device using the first and third Purkinje reflexes, so you’re close to the line of sight in the center. We then turn on the suction, send a jolt of electricity through, cut the cap- sulotomy, release the suction, and pull it out. In pulling the device out, the corneal wound compresses the silicone shell, so you come out through that same small wound.” According to Dr. Packer, pre- clinical studies have shown that Zepto capsulotomies are stronger than manual capsulotomies, which are stronger than laser capsuloto- mies. Additionally, it is perfectly round. The device received 510K clearance this year and is available now. “The price is [US]$175 for the disposable. The handpiece under the ring is all one unit with a cord that plugs into a box,” Dr. Packer said. “The box is a [US]$10,000 capital purchase, which is sig- nificantly less than a laser, but the reusable cost of [US]$175 is a little high for standard cataract surgery. I think there are two places where it may be used. One is in difficult and challenging cases for standard surgery, and the other is in the pre- mium refractive cataract surgery cases, where it might take the place of a femtosecond laser.” ApertureCTC ApertureCTC (International BioMedical Devices, Mt. Pleasant, South Carolina) is following in the footsteps of Zepto. “The technol- ogy is somewhat similar in that it’s a thermal device that creates the capsulotomy with heating,” Dr. Packer said. “A couple of key dif- ferences are that the tip design is stainless steel and does not require suction; it has two compressible stainless steel blades that form a perfect circle. When they’re in the elongated position, they can be introduced through a 2.2-mm inci- sion. There’s a little slide on the handpiece, which compresses the blades, and they form a circle. A current is run through the blades, which creates heat, and cuts the capsule tissue in milliseconds. There is no suction, however, the thermal heating element is insulat- ed from the anterior chamber envi- ronment. The anterior chamber is filled with viscoelastic during the procedure.” ApertureCTC is still in preclin- ical stages of development, with a goal of using it in humans for the first time next year. CAPSULaser CAPSULaser (Los Gatos, California) is a completely different concept. It’s a laser device that is a micro- scope attachment. “The laser is small and fits onto the bottom of the operating microscope,” said Richard Packard, MD , Wind- sor, U.K. “It can perform capsular openings from 4.5 mm to 6.5 mm. The capsular opening is created in 1 second following staining of the anterior capsule with a new formu- lation of trypan blue. In clinical studies of over 400 patients, there have been 100% free capsulotomy caps and no anterior capsule tear-outs. Comparing the results of accuracy of sizing, circularity, and centration on the visual axis to published data on femtosecond and manual capsulotomies shows a clear advantage for CAPSULaser.” Zepto capsulotomy system console Source: Mynosys Cellular Devices